In recent years, a broadcasting system has come to deal with various video signals. As to these different video signals, there are interlaced video signals which change a display screen in a cycle of 33 ms (milli-second), and progressive video signals which change a display screen in a cycle of 16.5 ms.
Moreover, in a broadcasting system, video signals, such as a video signal sent through a line or taken by a surveillance camera, are temporarily stored in a video server. The video signal stored in the video server is sent out from the video server.
When playing back the video recorded in the interlaced video signal, the screen of one sheet is outputted in a cycle of 33 ms. When playing back the video recorded in progressive video signal, the screen of one sheet is outputted in a cycle of 16.5 ms which are the time of the half in the case of playing back interlaced video signal. When carrying out playback control of the progressive video signal, it is necessary to perform control at intervals of the cycles of 16.5 ms. However, controlling at intervals of a half compared with the playback of interlaced video signal doubles processing load. As a result, other processing may affect the playback of a progressive video signal. Moreover, software becomes complicated when the video server deals with both the playback of interlaced video signal, and the playback of progressive video signal, i.e., when the video server deals with the plurality of modes in which the intervals of control differ.